Synthesis of mono and doubly alkynyl substituted ferrocene and its crystal engineering using –C–H···O supramolecular synthon

Mono and doubly alkynyl substituted ferrocene complexes, [Fc(CH2OCH2Ctriple bond; length of mdashCH)n], 2–3 (2: n = 1; 3: n = 2; Fc = ferrocene) have been synthesized from the room temperature reaction of mono and 1,1′-dihydroxymethyl ferrocene, Fc(CH2OH)n , 1a–b (1a: n = 1; 1b: n = 2) and propargyl bromide, in modest to good yields. These new ferrocene derivatives have been characterized by mass, IR, 1H, 13C NMR spectroscopy, and molecular structures of compound 2 and 3 were unequivocally established by single crystal X-ray diffraction study. The crystal structure analysis revealed that 2 and 3 consist of infinite 1D zig-zag hydrogen bonded chains and 2D microporous hydrogen bonded network of molecules, linked by intermolecular C–H···O hydrogen bonding. The molecular structures of both 2 and 3 are further stabilized by C–H···π interactions.